The Ultrasonic Dissector Facilitates
Laparoscopic Cholecystectomy L. Albert Wetter,
MD; John H. Payne, MD; Gerald Kirshenbaum, MD; Eileen F. Podoll, RN; Thomas Bachinsky, PA-C; Lawrence W. Way, MD
\s=b\ The ultrasonic dissector disrupts tissues in proportion to their fluid content by ultrasonically induced cavitational forces. Since sturdy tissues are spared, the instrument tends to follow tissue planes and to dissect fat and other soft tissues
selectively. We performed a prospective, randomized,
controlled trial in 73 patients comparing the safety and efficacy of a prototype ultrasonic dissector with that of electrosurgery and laser during laparoscopic cholecystectomy. Randomization was as follows: ultrasonic dissector, 37 patients; electrosurgery, 21 patients; and laser, 15 patients. The results were not different with respect to patient characteristics, amount of blood loss, technical difficulties, length of hospital stay, or return to work. Subjectively, the ultrasonic dissector was thought to be of special value in isolating the hilar structures, particularly when they were edematous or embedded in fat. The ultrasonic dissector disintegrated the fat, which was rapidly cleared up the suction channel, allowing the cystic duct and artery to be bared with less risk of injury. We concluded that the ultrasonic dissector has unique attributes that contribute to the ease and safety of laparoscopic cholecystectomy.
(Arch Surg. 1992;127:1195-1199)
of less pain, shorter hospitalization, less prom¬ and much faster rehabilitation, laparo¬ inent Because has become the scars,
a
scopie cholecystectomy (LC)
preferred gallstone disease. In general, however, LC is difficult than open cholecystectomy. Among the
treatment for more
technical differences between the two operations is the de¬ sirability of a much greater degree of hemostasis during LC. Even small amounts of bleeding, which would other¬ wise be inconsequential, may obscure the surgeon's view and make the dissection hazardous in areas such as the
Accepted for publication June 6, 1992. From the Department of Surgery, University of California,
San Francisco (Drs Wetter and Way); the Department of Surgery, Kaiser Hospital and the University of Hawaii, Honolulu (Dr Payne and Ms Podoll); and the Department of Surgery, Humana Hospital, Aurora, Colo (Dr Kirshenbaum and Mr Bachinsky). The authors have no financial interest in Valleylab Inc, Boulder, Colo. Neither they nor members of their families have been paid stipends as employees or consultants by the firm. Presented at the 63rd Annual Meeting of the Pacific Coast Surgical Association, Kauai, Hawaii, February 19, 1992. Reprint requests to Box 0475, Room 550-S, University of California, San Francisco, CA 94143 (Dr Way).
liver hilum. There are methods for handling this problem1; when it occurs, however, it is often more than a nuisance. There are two principal kinds of dissecting instruments currently used in laparoscopie surgery, ie, mechanical and heat energy dissectors. The former category includes scis¬ sors, graspers, and knives. The latter includes electrocautery and lasers, both of which deliver heat energy that vaporizes tissues.2 Although widespread use has demon¬ strated their effectiveness, electrocautery and laser do have shortcomings. For example, they are unselective in the sense that fibrous tissues are cut almost as readily as soft ones. Consequently, bleeding may result from unintended division of small vessels. Furthermore, both produce bothersome smoke. The ultrasonic dissector fragments cells by producing shearing forces from ultrasonically induced intracellular vacuoles.3 The vulnerability to ultrasonic disruption is re¬ lated to the fluid (water or fat) content of the cell, so soft tissues, such as adipose or hepatic tissue, are easily disrupted, while fibrous tissues, such as bile ducts or ves¬ sels, are not. In addition, no smoke is produced. We thought these properties might prove useful during LC. The ultrasonic dissector (Cavitron Ultrasonic Surgical
Aspirator [CUSA], Valleylab Ine, Boulder, Colo)
was
modified so that the handpiece fit through a laparoscopie trocar. After proving its effectiveness in pigs, we compared CUSA dissection with electrosurgical and laser dissection during LC. MATERIALS AND METHODS This prospective, randomized, controlled trial was carried out between January 1991 and May 1991 at three institutions: the University of California, San Francisco; Kaiser Hospital, Hono¬ lulu, Hawaii; and Humana Hospital, Aurora, Colo. Thus, the trial spanned a broad spectrum of surgical practice and patients. The five participating surgeons were experienced laparoscopists, each of whom had performed more than 25 LCs before the study was begun. In two centers (Kaiser and UCSF) electrocautery (Force two, mixed blend, Valleylab Ine) was used routinely for dissec¬ tion and hemostasis. In Humana Hospital laser (SLT laser CL 100 with a GRP8 laser scalpel probe; setting, 16 W) was routinely used. All patients under the care of the investigators who were scheduled for LC were asked to participate in the study, and all agreed to do so. The patients were admitted to the hospital on the day of surgery. The operation was performed with general anes¬ thesia, and carbon dioxide was used for the pneumoperitoneum.
Downloaded From: http://archsurg.jamanetwork.com/ by a University of Pittsburgh User on 10/07/2013
The patients were randomized to group 1 (the CUSA group) or group 2 (electrocautery or laser) by opening a sealed envelope once the decision to proceed with LC had been made in the op¬ erating room. A 12-mm trocar was inserted in the epigastrium to accommodate the CUSA handpiece. Except for the dissecting tool all patients received similar treatment, including a single preop¬ erative dose of cephalosporin for prophylaxis against infection. Electrocautery or laser was used for hemostasis when necessary in the CUSA group since the prototype model did not have elec¬
trocautery capabilities.
If the CUSA failed to perform the dissection adequately, the protocol allowed the use of any alternative mode of dissection af¬
and circumstances of the failure were documented. Time of discharge from the hospital was dictated by the clinical findings, and all patients were seen 1 month after surgery for follow-up. The study protocol was approved by the Committee on Human Research of each institution. A nonparametric Kruskal-Wallis one-way analysis of variance was used to compare the data in the treatment groups, and a probability of P
Laparoscopic Cholecystectomy L. Albert Wetter,
MD; John H. Payne, MD; Gerald Kirshenbaum, MD; Eileen F. Podoll, RN; Thomas Bachinsky, PA-C; Lawrence W. Way, MD
\s=b\ The ultrasonic dissector disrupts tissues in proportion to their fluid content by ultrasonically induced cavitational forces. Since sturdy tissues are spared, the instrument tends to follow tissue planes and to dissect fat and other soft tissues
selectively. We performed a prospective, randomized,
controlled trial in 73 patients comparing the safety and efficacy of a prototype ultrasonic dissector with that of electrosurgery and laser during laparoscopic cholecystectomy. Randomization was as follows: ultrasonic dissector, 37 patients; electrosurgery, 21 patients; and laser, 15 patients. The results were not different with respect to patient characteristics, amount of blood loss, technical difficulties, length of hospital stay, or return to work. Subjectively, the ultrasonic dissector was thought to be of special value in isolating the hilar structures, particularly when they were edematous or embedded in fat. The ultrasonic dissector disintegrated the fat, which was rapidly cleared up the suction channel, allowing the cystic duct and artery to be bared with less risk of injury. We concluded that the ultrasonic dissector has unique attributes that contribute to the ease and safety of laparoscopic cholecystectomy.
(Arch Surg. 1992;127:1195-1199)
of less pain, shorter hospitalization, less prom¬ and much faster rehabilitation, laparo¬ inent Because has become the scars,
a
scopie cholecystectomy (LC)
preferred gallstone disease. In general, however, LC is difficult than open cholecystectomy. Among the
treatment for more
technical differences between the two operations is the de¬ sirability of a much greater degree of hemostasis during LC. Even small amounts of bleeding, which would other¬ wise be inconsequential, may obscure the surgeon's view and make the dissection hazardous in areas such as the
Accepted for publication June 6, 1992. From the Department of Surgery, University of California,
San Francisco (Drs Wetter and Way); the Department of Surgery, Kaiser Hospital and the University of Hawaii, Honolulu (Dr Payne and Ms Podoll); and the Department of Surgery, Humana Hospital, Aurora, Colo (Dr Kirshenbaum and Mr Bachinsky). The authors have no financial interest in Valleylab Inc, Boulder, Colo. Neither they nor members of their families have been paid stipends as employees or consultants by the firm. Presented at the 63rd Annual Meeting of the Pacific Coast Surgical Association, Kauai, Hawaii, February 19, 1992. Reprint requests to Box 0475, Room 550-S, University of California, San Francisco, CA 94143 (Dr Way).
liver hilum. There are methods for handling this problem1; when it occurs, however, it is often more than a nuisance. There are two principal kinds of dissecting instruments currently used in laparoscopie surgery, ie, mechanical and heat energy dissectors. The former category includes scis¬ sors, graspers, and knives. The latter includes electrocautery and lasers, both of which deliver heat energy that vaporizes tissues.2 Although widespread use has demon¬ strated their effectiveness, electrocautery and laser do have shortcomings. For example, they are unselective in the sense that fibrous tissues are cut almost as readily as soft ones. Consequently, bleeding may result from unintended division of small vessels. Furthermore, both produce bothersome smoke. The ultrasonic dissector fragments cells by producing shearing forces from ultrasonically induced intracellular vacuoles.3 The vulnerability to ultrasonic disruption is re¬ lated to the fluid (water or fat) content of the cell, so soft tissues, such as adipose or hepatic tissue, are easily disrupted, while fibrous tissues, such as bile ducts or ves¬ sels, are not. In addition, no smoke is produced. We thought these properties might prove useful during LC. The ultrasonic dissector (Cavitron Ultrasonic Surgical
Aspirator [CUSA], Valleylab Ine, Boulder, Colo)
was
modified so that the handpiece fit through a laparoscopie trocar. After proving its effectiveness in pigs, we compared CUSA dissection with electrosurgical and laser dissection during LC. MATERIALS AND METHODS This prospective, randomized, controlled trial was carried out between January 1991 and May 1991 at three institutions: the University of California, San Francisco; Kaiser Hospital, Hono¬ lulu, Hawaii; and Humana Hospital, Aurora, Colo. Thus, the trial spanned a broad spectrum of surgical practice and patients. The five participating surgeons were experienced laparoscopists, each of whom had performed more than 25 LCs before the study was begun. In two centers (Kaiser and UCSF) electrocautery (Force two, mixed blend, Valleylab Ine) was used routinely for dissec¬ tion and hemostasis. In Humana Hospital laser (SLT laser CL 100 with a GRP8 laser scalpel probe; setting, 16 W) was routinely used. All patients under the care of the investigators who were scheduled for LC were asked to participate in the study, and all agreed to do so. The patients were admitted to the hospital on the day of surgery. The operation was performed with general anes¬ thesia, and carbon dioxide was used for the pneumoperitoneum.
Downloaded From: http://archsurg.jamanetwork.com/ by a University of Pittsburgh User on 10/07/2013
The patients were randomized to group 1 (the CUSA group) or group 2 (electrocautery or laser) by opening a sealed envelope once the decision to proceed with LC had been made in the op¬ erating room. A 12-mm trocar was inserted in the epigastrium to accommodate the CUSA handpiece. Except for the dissecting tool all patients received similar treatment, including a single preop¬ erative dose of cephalosporin for prophylaxis against infection. Electrocautery or laser was used for hemostasis when necessary in the CUSA group since the prototype model did not have elec¬
trocautery capabilities.
If the CUSA failed to perform the dissection adequately, the protocol allowed the use of any alternative mode of dissection af¬
and circumstances of the failure were documented. Time of discharge from the hospital was dictated by the clinical findings, and all patients were seen 1 month after surgery for follow-up. The study protocol was approved by the Committee on Human Research of each institution. A nonparametric Kruskal-Wallis one-way analysis of variance was used to compare the data in the treatment groups, and a probability of P
